Motor vehicle



I I 9 1 arch 8 w. P.

MOTOR VEHICLE Filed May 25, 1925 Patented Mar. 8, 1927.

UNITED sTATEs FATE NT OFFICE.

win-mu r. xnnimmr, or mew YORK, N. Y.

moron vnmcm.

Applicationflled Kay 25, 1925. Serial No. 32,034.

This invention relates to various novel ,features of steering equipment embodied in portance of which increases in proportion to the lengthening of such vehicles and is ace cent-uated under congested traflic conditions in cities and in going around short curves on rural highways.

Among the objects of this invention when applied to a tractor united to a semi-trailer constituting a unit vehicle are-to provide or the steering movement of the rear or trailer wheels controlled by the turning movements of the tractor part of the vehicle with relation to the trailer part, and also to provide that the changing'steering movements of the rear wheels shall be varied in unequal degrees for equal angular changes of the tractor with relation to the trailer in the general steering movement of the We hicle, and further to insure that the path'of the trailer wheels shall follow. a predetermined course which shall be different for different lengths of vehicles governed by a steering mechanism actuated by changing angul'arity between the tractor and trailer..

' Another object of this invention is to provide in'a six wheel vehicle of the tractor and semi-trailer type a. steering movement of all six wheels whlch shall be automatic inresponse to'the initial angular movement given a to the front wheels by turning a single wheel mounted on a-conve'ntional steering post in the hands of an operator,-the path of the rear wheels following a predetermined course in a'manner to insure thatthe rear part of the vehicle shall follow the path taken by the front part, particularly in passing through openings or narrow spaces, provision being made in the steering equipment of such a vehicle for its articular overall length. A further object is to provide in a vehicle of the type referred to that when passing from one street to another at right angles or in turning a sharp right angle Y steering compli sh jointly corner, the turning movement of the rear wheels shall be so delayed until they have advanced forward to the position at which the rear axle of the tractorcommenced its turning movement, aroundsuch a, corner, the purpose of this delayed steering being to prevent the trailer axle and wheels in-such an instance taking a short cut around the corner as would be the case in a conventional vehicle of this type not provided with such equipment as is covered by this invention.

A still further purpose of such delayed trailer steering is to enable along vehicle of thetype described turning around a right angle corner, ,thus

avoiding the necessityof the tractor having to make a wide circuit to insure the clearance of the rear end of the vehicle from contact with such a right angle corner. Such a steering equipment in the type of vehicleto make a short radius referred to'will insure that a long vehicle in passing another on the short or sharp curves of a highway will not sideswipe with its rear end the passing vehicle, but will adhere to the of the vehicle in making such a turn. An additional advantage in the use'of the steermg equipment covered by this'invention is that the rear or trailer axle may be placed close to the rear end of the body of the vepath or course taken by the front end hicle and thus eliminate the overhang ofth'e body beyond the rear axle now customary in. vehicles, and particularly inor' large passenger capacity- 1Q These and other-objects it is aimed :to ac-". I

and separately aswill appear from the detailed description herein.-

conventional motor buses after set forth.

Under the current development taking a place in the application of motor vehicles to freight and passenger transportation in congested cities and over interurban highways, there is an increasing trend towards the use of lar er capacity vehicles operated by a single driver with the object of transporting a greaterquantity of freight or an increased numb duced outlay for operators expense, and to effect concentration and reduce traflic congestion. In accomplishingthese purposes,

er ofpassengers with a re-* can . have been exceeded and resort has been had else.

to various improvements in design and construction, oneof which has been the employ ment of two rear load axles placed relatively close to each other. Another development has been the employment of a short wheelbase tractor having attached thereto a semi-. trailer tor car mg the load, the front end of such trailer being attached near the rear end of the tractor by means of a swiveling fifth wheel connection. The increased overall length of vehicle resulting from such practices has introduced steering problems in shooting the short turning of each vehi: In the former type of development "net-referred to increased turning facility as been sought by increasing the steering angle of the front axle steering wheels which provided alimited form oil remedy. in the tractor semi-trailer it no of vehicle recourse has been had to e employment or a stcerin axle towards the rear end of the trailer. some instances this takes the form at a rigid or straight anle connected to the body of the vehicle by a filth-wheel so that this rear axle as a whole may turn in its steerin movements. This practice is exempliiie I in fighting such a rear steering axle 1s manipulated by a special operator. In other instances suc an axle has been made to turn in its steering movements by connection with the tractor, the change in steering movement resulting from angular changes talrin place between the tractor and the semi-trai er. in other instances a steering axle of the pivoted wheel i go similar to that conventionally employed at the front oi automobiles has been-applied to the rear end of such semitrailers steering movements oi the piv otnd wheels being controlled by rods and lover connections to the tractor part so that the general steering of the vehicle the changes taking place between the tractor and the trailer lave been made use all (iterate the rear steering wheels by the direct mechanical connections referred to.

in all these improvements there is a re maining defect resulting in the fact that the rear wheels, and more articularly the rear body part of the vehic e, moves through a path or course in. following the forward part oi the vehicle which is materially difierent from that talren by the front part, and this is particularly accentuated comparing the course or the rear part at the vehicle with that oil the fore part in turning around a apparatus where notes-er sharp right angle turn with the tractor and semi-trailer type of vehicle. This is due to the laclr of any provision introduced between the tractor and the semi-trailer for varying the ratio of angular movement of the rear steering wheels with relation to the angular movement of the tractor with the trailer, which remains constant in so far as the dimensions of the leverage system emplo ed in these connections remain constant. This condition is aggravated when the same steering connection system is employed in vehicles having different lengths of wheelbase between t. e rear axle of the trailer and therear axle of the tractor. My invention consists 0t introducing into such a tired or invariable system of steering connection a varying leverage mechanical movement for changing the angular ratio referred to,.and which means in one'o'i its forms may consist of a cam and lover memovement or the lever may be pro- 1 duced y a rotating cam 1n contact therewith, the contour of which cam to be deco signed in relation to the-desired rear steering u w ieel movement at the dillerent points of its rotation, and the rotation of this cam to be redacted by the turning or angular movement of the tractor with relation to the trailer.

The particular location of this variable motion mechanism is immaterial and it may be laced either in the forward part of the trar e'r inpronimity to the connection between the tractor and the trailer, or it may be located on the rear axle adjacent to the steering wheels. v

The best known embodiment of my invention is shown in the accompanying drawing, in which: v

Fig. 1 is a plan view of a running gear of an automobile tractor connected by a fifthvwheel to a semi-trailer running gear, constituting together a six wheel unit vehicle, and showing also the steering arrangements.

Fig. 2 is a side elevation of the same trad tor and semi-trailer running gear illustratingthe connections between them.

Fig. 3 illustrates in side view and in detail a steering gear mechanism mounted on the semi-trailer rotated by gearing mounted upon the tractor fitthheel connection to the semi trailer.

Fig. dis a vertical illustration of the rotating steerin gear cams geared to a rotating sector by which they are actuated and which appear in transverse view talren across the line (3-D of Figs. 1 and 5. 1

Fig. 5 is a plan view of the gearing connections between the, tractor and trailer for operating the teering mechanism of the s j trailer shown vertically in El.

1g. 3; this being a g.

flat plane of a steering: gear cam having a curved profile indicating the contour of its workin e contour of the cam and 2, and the connections between the trac-,

tor and trailer elements of this unit separately illustrated in Fig. 3, hasthe automobile tractor runnin gear A and semi-trailer runmng gear B. he tractor A has a front axle 1 with steering wheels 2, mounted as commonly used on automobiles, governed and controlled by the post and handwheel 3, and a driving axle 4 with driving wheels 5 mounted thereon.-

The tractor A is connected to the semi-trailer B through a fifth-wheel mechanism 6, 7 and 8, more particularly illustrated in Fig. 3, 6 being a top ring having a cross plate 9 carrying kmg bolt or pivot 10 as shown in Fig. 1 and more particularly in Fig. 5, the pivot 10 fitting into a central opening in base plate 7. These parts 6 and 9 are attached to the sem1-trailer permitting them to swivel horizontally around and upon base plate7, WhlCh is attached to the brackets 8 mounted on the tractor A b means of a rockshaft 11, by which rockshag mounting the two plates 6 and 7 can be rocked or partially rotated around the horizontal axis of the rockshaft 11. The semi-trailer-B is supported in the rear by .a steering axle 12 having steering wheels 13 pivoted to axle 12- at vertical pivots 14, the wheels 13 being rotated around vertical pivots 14 by steering levers 15 which are linked together by a cross connectitgg rod 16 actuated by a rocker a'rm'17 pivo at 18 to axle 12, the connection between the cross rod 16 and the rocker arm 17 being made at the pivot 19.v The rocker arm 17 is rotated on pivot 18 through longitudinal connecting rods 20 at theirforwardends atthread to be described more tached to and actuated in 'a'fore and aft .movement by bell crank cam lever 21 in conv tact with rotating-cams 22 through a. roller 23 or other projection of the cam lever into spiral grooves on rotatingcams 22. These cams 22 are of the having grooves resembling a coarse screw particularly in connection with Fi .'.6 and 7. These cams 22 are mounted on t e vertical shafts 24 supported by hearing brackets 25 mounted on semi-trailer frame 26, the bellcrank cam levers 21 aligned with and actuated by rotating cams 22 are also mounted on frame 26 by trunnion brackets 27. Keyedrto the vertical shafts24 at their upper'ends arepinions 28 aligned to mesh with the gear sector 6 wrapped around a conventional steering cylindrical or drum typ .der or drum 22 29, which sector is a part of base plate 7 of the fifth wheel 6, 7 tractor A on its frame 30.

Fig. 4 is a vertical illustration taken across the line C-D, Figs. 1 and 5, showing the relative positions of the cylindrical cams 22, shafts 24 and pinions 28, all of which are mounted on the semi-trailer B aligned to'mesh with the actuating gear sector 29 which is mounted on the tractor A, so that Whenthe tractor A is moved with relation to semi-trailer B'the motion of the ear sector 29 rotates the pinions 28 which impart a corresponding rotating motion to cylindrical cams 22.

Fig. 5 is a plan view of the geared connections illustrated in Figs. 3 and 4 which shows the gear sector 29, which is mounted on tractor A, meshed with the pinions 28, which are mounted on trailer B, so that when rotary motion is imparted to gear sector 29'by movement of the tractor A with relation to semi-trailer B .a corresponding rotary. motion is imparted to pinions 28. This plan view illustrates the top iling 6 with its cross [glate 9 and pivot 10: superimposed upon. ase plate 7 from the rear of which projects the ating the pinions 28.

Fig. 6 is afiat plane outline 'of a cam, the

working contour E-F of which is developed in accordance with the path through which it is desired to have the {rear steering wheels 13, Fig. 1, roll in follouiilpg the path of the driving wheels 5, Fig. 1 his contour E-FG applied so as to accomplish this gear sector 29 actuand 8 attached to the f ill) purp'ose'as lllustrated at '22 in Fig. 3 guides the movement of the bell crank lever 21 which in turn through the connections 20, 17, 16 and 15 as shown in Fig.1 effects the desired steering movements of the rear steering'wheels 13. I

For further illustrative purposes the contour EF--G shown as a plane in Fig. (i is indicated in cylindrical or drum form in Fig. 7, which working contour isthus made to determine the outline of a grooved spiral path on the surface of a-cylinder or drum such fasthat shown at 22 in Fig. 3, into 'which' one end of the bell crank lever 21 is fitted by, means of a roller 23 or other projectionifromthe'end of this lever 21 so that the motion produced in the lever 21 is in accordance with the groove on the cyhnwhenever the cylinder 22 is rotated to effect this movement. The steering operationsas shown in this particular embodiment of my invention would be as follows:

The tractor A, Fig. 1, having articulated front road wheels 2 and the conventional steering post and handwheel 3, in thehafids of an operator can be angularlty with semi-trailer B when moving; along a highway, relative motion bemade to change lts censes the gene sector 53% causes the steam? on nngnlnr movement in means which will vnr tween the trector A, semi-trniler to rotnte the pin ions which in tnrn rotate the. come 22 and thereby import verticei motion to the upper pert oi the hell crnnh lever '21, the lower end of which sininlteneonsly moves hnclrwnrois or iorwnrol to e degree depenoing upon. the gro'ovecl course or path in the rototing cyhntiricnl come 22. This motion of the hell crank love: 21 is importccl' to the rocker arm 1? on he rear axle 12 through the longitudinal connectin rocker erm. 17 through its connection at pivot/19 moves the connecting rod 16 transversely which through steering levers 15 wheels 13 to rotote pivots 14: thus causing these wheels 18 which is inoliceted out L, Fig. i, The steering enguisr movement of the trector A. with relation to the scnii troiler it is intiicnteri h the single it. shown "hetween nnis if; oi the ctor A the nnis J J or the semi-train it there were no verinhle menne ct chcngging the reletion oi the nngle L to the magic K incorporntecl in ing connections between the ti'ector it end semi-treiler ii for etch equni increments in the engie ii thorn wonlol he corresponding equni increments in the nnglo L, hot with n inenne oi vnrintion introrincei into the steering connections oi the semitroiier B ns e'nemp iiicti the cone end lever mechnnisrn 22 tint 21 this invention provides for e the angle L with relation to the single in eny ratio which may he prenetermincrl, that such predeterhe hnsefl upon the pnrticulnr erounol the vertic niinntion con path thron h which it is desironto hnve the steering w eeis l3 ass in following the tractor wheels 5, nn this determinetion in turn would he iorrnulnted upon the ieng th oi the wheelhnsc between the troctor driving stile einnfl the eemi trniler nitie i2.

Whiie the figures, illustrating e particular einhotiinnent oi this invention, show the rent steering nnle to he oicthe pivoteii wheel type, tries oi other design, snch es those pen forming steering tunctic-ns icy rotntion shoot it centrci Wis, me he empioveti es elements incorpornteoi in t iis invention.

This com nncl lover t pe of mechenisni has been made use oi in t e toregoing specificntions nni drawings on illustrative oi the principles oi this invention, but it must he unnerstootl that other forms of mechnnicni devices cnpehle of converting e not amounts of movement into corresponn l verichle exnonnts oi movnt he one enoi tor there that these new hoiocetedl nt iiiiierent pieces within the limits oi the inechnnicet connections employed to trencniit the nctn= ntin movements of the trector to the treiier steering wheels,

I em cwere that prior to my invention rods 20, end thethe steer 'nism nctnetexi in corn nnii' llever steerin mechanisms hnve incite end cipgiie to the st ering oi nntornohiles this, pnrticulcr mechanism is not covered by my invention out li clnini and; desire to secure by Letters Petent is:

i, in en entoncohile consisting oi attractor tienihiy connected with n semi-treiier, said semi-treiler equipped with a rear axle hoving steeringv wheels mountcdl on pivots for steering angular movement and s mechanical connection interposed between said tractor and said steering wheels to change the steering angle of said wheels when the ennler relation of snidl tractor to said trniler is chengedl, moons incorporated in snid mechenicei connection to vary the degrees oi nngnler movement of said steering wheels for equal singular changes in movement of the tractor with relation to the trniler;

2, in on entomoloiie consisting of n trootor iienihiy connected with e, semi-treiler, snirl scnii-trniler cqni pod with e. rcnr axle hcving steering whee s mounted on pivots ior steering nngulor movement enol at mechnnicni connection interposeci between snidl trnctor end shit steering wheeis to change the steerin tangle of snicl wheels when the onguler re stion of said treotor to soul eel, it com onel lever mechansniii niechsnicel connection to prorliice'e verinhle nnguler change in said steering wheels fiependin on the contour of the coin in seici cnrn end iever mechanism.

3. In en nutomobiicconsisting of n tractor flexibly connected with s semi-treiler, snid semi-treiier uippei with at rear nxle having steering w eels mounted on pivots for steering nler movement endi e mechenicnl connection interposed between said trector end seii steering whwls to chenge the steerine nn gle oi send wheels when the enter refietion oi seici tractor to snicl treiier is chnn eat, on oscillating lever incohnnisrn ectuntc nt n vcriehlc rate or movement hy the contour oi o. rotating; onto roteieri in eeicl mechenicni connection hetween the trector endl the steering wheels oi the treiien.

A steering control system tor guiding the rcnr wheels of eemi-trniier vehicles drown in? entoinotive trectors incoinoreting e verieh e motion mechenism to import varyin amounts oi enter chnnge to the rear steer wheels oiseiii semi-triniier in re sponse to eqnnl increments of changing engnlnrity between seid trector end semitreiler.

5. in on nntornohiie consisting of n tractor flerihiy connection to e -trniler having nnie wheels nrrengeti for I through cngninr changes in relntion to Elfilim semi-trniier enxi trniier is chcng s, niechsnlonioonnection in hetween snarl trnctor and semi rcer enle to trsnsnnt relative angels-r vement iii) UNI:

between saidtractor and said semi-trailer to' movement between the tractor and semiactuate the steerin angular changes of said vtrailer.

rear axle and whee s, a variable ratio move- In testimony whereof, I have si ed my J0 ment transmission mechanism incorporated name to this application, this 231- ;day of 6 in said mechanical connection to produce May, 1925.

unequal angular movement of the rear axle and wheels in response to equal angular WILLIAM P. KENNEDY. 

